Here are the recommendations from ALFA 1750 when using one DHLA 40H on a stock 1200 engine:

8383.28 Choke / Venturi
7448.3 Auxiliary Venturi
7484.125 Main jet
7644.62 Idle Jet
7851.45 Pump Jet
7772.11 Main Emulsion Tube
7845.200 Air Corrector

8811.150 Needle valve (150 standard with rebuild kit)

7850.xx Idle Holder for Emulsion Tube (dunno if this was necessary)
DHLA 7850.xx idle holder numbering makes no sense
Leaner Normal Richer
.5 .10 .9 .4 .1 .3 .6 .7 .2 .8
As per the article from VW Vortex, I purchased .10 (leaner) and .8 (richer) so we would have something to play around with.

The engine apparently started out as a JDM rebuilt long block that was bored .40 over. It had been robbed of its head and got it in trade for some assorted car parts. Years ago I got a head from ddgonzal and got it rebuilt through a friend of mine. The DHLA 40H was a "trunk find" that was stashed in a Morris Minor parts car that I bought and I got a good price on a used intake manifold. I'm telling you this because this carb jetting process ain't cheap; I might end up with more in the carb that I have in the engine. Again, I do not know how this is going to work, but will keep you posted.